Optical waveguides are structures that are designed to guide and control the propagation of light waves. These waveguides are commonly used in various applications such as fiber optic communication systems, sensors, and integrated optics devices. They are usually made of materials with high refractive indices, allowing for total internal reflection of light within the waveguide. Optical waveguides can be used to confine and manipulate light in a controlled manner, enabling various functionalities in optical systems. Research in optical waveguides focuses on improving their performance, designing novel waveguide structures, and exploring new applications in photonics and telecommunications.